N IMPROVED EFFICIENCY PERMANENT MAGNET BRUSHLESS DC MOTOR PV PUMPING SYSTEM

Abstract

This paper presents the optimal operation of a photovoltaic pumping system.
The operation of a permanent magnet brushless DC motor driving a centrifugal
pump is investigated. The motor is controlled through a hysteresis current loop
and an outer speed loop with a PI type controller. The proportional and
integral gains are set to their optimal values. In order to optimise the overall
system efficiency, a Maximum power point tracker is also used. Simulation is
carried out by formulating the mathematical model for the photovoltaic source,
MPPT, motor and pump load. System performances are investigated under
different levels of solar insolation. The effectiveness of the proposed controller
is also demonstrated.